“The opportunity to save the Trump presidency is to make business progress and stop focusing on the media,” Ackman said, adding that Trump as has been “picked on.”

After the election, Ackman said that he woke up “bullish” on Trump because the country hasn’t had a pro-business president before. However, he doesn’t think that the American people could tolerate another four years of nothing happening. For Trump, his first plan of action would be to hold a press conference.

“I’d get up in front of the American people. I’d say, ‘look I’m delighted this investigation has been launched. Let’s get to the facts… I’ve got a country to run.'”

Infrastructure led by the private sector

After he resets his message, he should launch “the most significant infrastructure program” and spend every dollar incredibly carefully.

Ackman believes there would be bipartisan support for an infrastructure bill. And the private sector should take the lead. He went on to compare Amtrak, a government-run enterprise, to Canadian Pacific, a Canadian railroad company run by an American CEO. He said the railroad industry in the private sector is efficient and well-maintained.

“What he needs to do is make progress for the country so that way he becomes too essential for people to get rid of him.”

And health care reform is not the way to start.

“Every president seems to start with health care, and it destroys pretty much every presidency,” he said. “Infrastructure and corporate tax reform are straightforward. I don’t think it’s controversial.”

It’s about taking small steps.

“It’s like running a successful hedge fund and having a big drawdown. It’s one step at a time. Make progress.” Ackman said. “You can’t accomplish everything at once. You start with the easiest thing for which you have the most support.”

The third thing he’d tackle — after infrastructure and corporate tax reform — would be personal taxes.

— Julia La Roche is a finance reporter at Yahoo Finance. Follow her on Twitter.